Use this chart to compare the elevation mapping options.
1. Pre-Sales
Help me review the data products.
I plan to drill a well on my property, will your groundwater data help me?
Yes and no. While the data can be used to identify good places to drill wells and identify flow direction to help identify the source of groundwater contamination, these services are best left to qualified professionals. The average landowner will not be able to correctly interpret or make use of this information on their own.
What’s raster and vector?
“Raster” refers to data made of pixels, like our orthophoto. Common raster file types you’ll find on our website include JPG, MrSID, GeoTIFF and ECW. “Vector” refers to data made of points, lines, polygons, and often includes text elements as well. Common vector file types you’ll find on our website include SHP, DWG, and DGN. […]
What format is groundwater data offered in?
Moraine groundwater are presented as asc files (ASCII grid). The asc file is a raster dataset similar to an image, where each pixel value represents an elevation value rather than a colour. Each of the asc files represent the elevation where you would find the various levels of substrate (e.g. Kettleby Till) along with the […]
What are the intervals of the contours?
The contours provided in tiles by FBS on MapWarehouse are in 1m intervals. In any area where high resolution orthophoto is available, it is usually possible to produce a more detailed elevation model. Contact us for a quote.
How accurate is the elevation data?
In the 2002 Golden Horseshoe data set, the horizontal and vertical accuracy is +/- 40 cm, and +/- 80 cm for the 2002 Simcoe-Kawartha data set. This means that the difference between the true elevation on the ground compared to what’s shown in the digital file can be as great as 40 cm or 80 […]
What’s floodplain mapping?
Floodplain mapping defines the limits of the Regulatory Floodplain for a particular watershed, used for regulatory purposes. These maps are produced and maintained by the TRCA (Toronto and Region Conservation Authority) for watercourses in the greater Toronto area, showing properties, topographic information and high water levels. Floodplain mapping was compiled photogrammetrically from 1/10,000 aerial photography […]
Where can I find historical imagery?
MapWarehouse has digital photo dating back to 2000. Older photo taken on film can be sourced on a case by case basis by contacting our customer service.
Is orthophoto different from aerial photo?
Yes. Orthophoto is produced by manipulating aerial photo to correct for movement of the aircraft and variations in the camera angle. Orthophoto has a top-down perspective and uniform scale, just like a map. Aerial photos are the original, unprocessed images. While they appear to be taken from an overhead viewing angle, they will inherently contain […]
How is the data projected?
Data is in UTM NAD83(original) in most cases, Zone 17N unless otherwise specified. While converting datum and projection settings for vector files is a simple task for most users, the same operation with raster data like orthophoto may require a higher level of expertise. Conversion to other datums such as MTM NAD27 Zone 10, which […]